David Cameron is keen on plans to encourage private sector investment in the roads network by allowing them to charge tolls in return for building and running new motorways, trunk roads and lanes.

Drivers who use motorways and trunk roads could also pay a higher level of road duty, while those who stick to B-roads and single-lane A-roads would get a cut.

However, the Liberal Democrats – and Tory ministers in the Department for Transport – are understood to be cool on the proposal, arguing motorists are unlikely to welcome the idea of new tolls and charges.

A senior Government source admitted it was unlikely that significant progress would be made before the next election in 2015.

‘Have you seen how long it takes to build a new road in this country?’ the source said.